Plastic recycling: Challenges and opportunities

Abstract

This review offers an in-depth exploration of current strategies for recycling plastic waste, focusing on mechanical, chemical, and energy recovery methods. It situates these strategies within the context of modern practices by examining ongoing research methodologies and specific case studies related to various types of plastic waste. The global crisis of plastic waste, along with various pre-treatment methods, is thoroughly discussed. The section on mechanical recycling details the processes applicable to different plastics, highlighting key challenges such as thermo-mechanical issues, the use of fillers to enhance certain properties, and material degradation over time. This discussion includes polymers such as polyethylene terephthalate (PET), low-density polyethylene (LDPE), high-density polyethylene (HDPE), polypropylene (PP), and polystyrene (PS). Chemical recycling is analyzed through advanced techniques like pyrolysis, catalytic pyrolysis, solvolysis, and gasification, presenting the state-of-the-art in this field. Additionally, the review touches upon energy recovery and the challenges associated with it. Conclusively, the study delves into the applications of recycled plastics and outlines future challenges. Overall, this review aims to provide a thorough overview and practical guidance on the recycling of plastic waste, offering essential insights for further development in this area.